The slim, bright crescent, known as the Lunar Horizon Glow (LHG) was glimpsed several times during Apollo missions. This picture was taken with the Clementine spacecraft, when the sun was behind the moon. The white area on the edge of the moon is the LHG, and the bright dot at the top is the planet Venus. There is a very, very thin layer of gases on the lunar surface that can almost be called an atmosphere. Technically, it's considered an exosphere. Several elements have been detected in it....
